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This plot:

was created using the following R code:

plot (q9e~q8, type = “n”,
xlim = c(1,13), ylim = c(1,13),
cex.lab=1.25,cex.axis=0.75,
col.lab = “#333333”,
xlab = “Obama job grade”,
ylab = “Congressional job grade”,
xaxt =”n”, yaxt=”n”,
main=”Obama and Congressional 100 day job grades”)

abline (or,lwd=2,col=”red”)
abline (od,lwd=2,col=”blue”)

axis(1,at=c(1,2,3,4,5,6,7,8,9,10,11,12,13),
lab=c(“A+”,”A”,”A-“,”B+”,”B”,”B-“,”C+”,”C”,”C-“,”D+”,”D”,”D-“,”F”),
col.lab=”#333333″, col.axis=”#333333″, tck=-0.02, cex.axis=0.75)

axis(2,at=c(1,2,3,4,5,6,7,8,9,10,11,12,13),
lab=c(“A+”,”A”,”A-“,”B+”,”B”,”B-“,”C+”,”C”,”C-“,”D+”,”D”,”D-“,”F”),
col.lab=”#333333″, col.axis=”#333333″, tck=-0.02, cex.axis=0.75)

text (5,6, “Democrats”,col=”blue”)
text (4,9.5, “Republicans”,col=”red”)
text(3,1,”Source: CNN/ORC Poll, April 2009″,col=”#777777″,cex=0.75)